Bits & Bytes: Week 4, II and III (DNS & DHCP)

Question 1

What type of Defined Resource Record is used to direct traffic from one domain name to another?

Answer 1

a CNAME record

Question 2

This type of Defined Resource Record is used to point a certain domain name at a specific IPv4 IP address

Answer 2

an A Record

Question 3

A single ___________ is configured for one ___________ but a _____________ can have many ___________

Answer 3

A Record, domain name; domain name, A Record

Question 4

When a client request receives a server response for one domain name containing multiple IP addresses which it iterates through for each request.

Answer 4

DNS Round Robin

Ex.
Server sends first client: 1st IP, 2nd IP, 3rd IP
Server sends next client: 2nd IP, 3rd IP, 1st IP
Then: 3rd IP, 1st IP, 2nd IP
and loop

Question 5

What is the logic behind dns round robin?

Answer 5

Traffic to a domain’s IP addresses will be fairly balanced

Question 6

What’s the difference between an A record and a Quad A Record (AAAA Record)?

Answer 6

A Records are for IPv4, AAAA Records are for IPv6

Question 7

Which defined resource record type would redirect a server from microsoft.com to www.microsoft.com?

Answer 7

the CNAME resource record

Question 8

What does CNAME stand for?

Answer 8

Canonical name

Question 9

ACRONYM:

MX Record

Answer 9

Mail Exchange Record

Question 10

This resource record is used to deliver e-mail to the correct server

Answer 10

MX records

Question 11

ACRONYM:

SRV Record

Answer 11

Service Record

Question 12

This resource record is used to define the location of various specific services

Answer 12

Service Record

Question 13

Which resource record has a field that’s entirely freeform?

Answer 13

Text Record

Question 14

Which resource record can be used to communicate data not originally intended to be communicated via DNS?

Answer 14

Text resource records

Question 15

What are used to demarcate where control moves from a TLD server to a an authoritative server?

Answer 15

Domains

Question 16

ACRONYM:

FQDN

Answer 16

Fully Qualified Domain Name

Question 17

How many levels of a domain, in total, can DNS support for a single FQDN?

Answer 17

127 levels

Question 18

How long can an individual section of a domain name be?

Answer 18

63 characters

Question 19

What is the maximum number of characters allowed for an entire FDQN?

Answer 19

255 characters

Question 20

Zone files are simple configuration files that declare what?

Answer 20

Resource Records for a particular DNS zone.

Question 21

These allow for easier control over multiple levels of a domain.

Answer 21

DNS Zones

Question 22

ACRONYM:

SOA

Answer 22

Start of Authority

Question 23

What declares the zone and the name of the name server that is authoritative for it?

Answer 23

the Start of Authority resource declaration

Question 24

What type of zone files allow DNS resolvers to request an IP and receive the FQDN associated with that IP in the response?

Answer 24

Reverse lookup zone files

Question 25

ACRONYM: PTR

Answer 25

Pointer Record

Question 26

What type of record resolves an IP to a name?

Answer 26

a Pointer record

Question 27

Which three things are unique to a network and which is unique to a node out of the DNS server, IP Address, Gateway router and Subnet Mask?

Answer 27

The DNS server, Subnet Mask, and Gateway router are usually unique to a network, while the IP address is unique to a node.

Question 28

ACRONYM: DHCP

Answer 28

Dynamic Host Configuration Protocol

Question 29

This is an application layer protocol that automates the configuration process of hosts on a network.

Answer 29

Dynamic Host Configuration Protocol

Question 30

client devices like desktops or laptops or even mobile phones do not need a ________ IP address.

Answer 30

Client devices don't need a static IP address

Question 31

What enables the configuration of a range of IP addresses for use by client devices?

Answer 31

Dynamic Host Configuration Protocol dynamic allocation

Question 32

What's the main difference between dynamic and automatic allocation?

Answer 32

Automatic IP allocation will remember a device and try to assign it the same IP if possible when in range. Dynamic allocation doesn't keep track of devices.

Question 33

Manually specified pairing of an IP Address with a MAC number/specific device

Answer 33

Fixed Allocation

Question 34

ACRONYM: NTP Servers

Answer 34

Network Time Protocol Servers

Question 35

This type of server is used to keep all computers on a network synchronized in time

Answer 35

Network Time Protocol Servers

Question 36

On which TCP/IP network layer will you find DHCP?

Answer 36

The application layer

Question 37

What is the process used by a DHCP configured client to get information about a network's configuration is what?

Answer 37

DHCP Discovery

Question 38

What does a client broadcast to a DHCP server when it would like to be assigned an IP address?

Answer 38

a DHCP Discovery Message

Question 39

A UDP datagram containing a DHCP discovery message always has which two ports as its destination and source?

Answer 39

Destination: Port 67 Source: Port 68

Question 40

Where would you find the DHCPDISCOVER message?

Answer 40

Encapsulated in a UDP Datagram

Question 41

The IP datagram containing the UDP DHCPDISCOVER datagram always has which two IP addresses as its destination and source?

Answer 41

Destination: 255.255.255.255 Source: 0.0.0.0

Question 42

Which port does a DHCP Server listen on for IP address requests from clients?

Answer 42

Port 67

Question 43

From which port does a client always send a broadcast request for an IP address?

Answer 43

Port 68

Question 44

What message is sent with a destination port of 68, and source port of 67, a destination broadcast IP of 255.255.255.255 and a its own source IP?

Answer 44

a DHCPOFFER message

Question 45

What is sent in response to a DHCPOFFER message?

Answer 45

A DHCPREQUEST message

Question 46

How does a client device know that a DHCP message is meant for it?

Answer 46

The DHCP message has a field containing its MAC address.

Question 47

What is the client telling the DHCP Server when it sends a DHCPREQUEST message?

Answer 47

The client is saying that it accepts the IP address that the DHCP Server offered.

Question 48

What is sent in response to a DHCREQUEST message, thereby completing the DHCP discovery process?

Answer 48

a DHCPACK Message

Question 49

What begins when a client starts using the IP address it was assigned by a DHCP Server?

Answer 49

A DHCP Lease

Question 50

How long does a DHCP Lease usually last?

Answer 50

A few days or less